M&M Cookie Bars
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These M&M cookie bars are loaded with M&M candies, made with browned butter, and lots of brown sugar and vanilla. You can totally customize these M&M bars too! They are super easy to throw together and made in one bowl.
When it comes to desserts I’m all for the fancy, the frosting topped, covered in sprinkles- but then sometimes you just need a simple fast dessert that will knock anyone’s socks off don’t you?
That’s what these M&M cookie bars are going to do for anyone you give them too. Socks everywhere.
I’ve brought these M&M bars now to a Superbowl party, an engagement party, and dinner with friends. All gone. All scrambling to get the last one. These cookie bars are basically a blondie. A crazy good delicious blondie.
What Are Blondies Made Of?
Blondies are basically a brownie but no cocoa powder is used. Vanilla is substituted for the cocoa instead.
They are made from some pretty typical pantry ingredients: flour, brown sugar, vanilla, sugar, butter, eggs, and a leavening agent (baking powder, baking soda or sometimes both).
What is brown butter?
These M&M cookie bars are simply awesome because of one ingredient – browned butter! No it’s not butter that’s gone bad! It’s butter that’s basically been toasted on the stovetop. When you brown the butter, the water cooks off and the milk solids in the butter caramelize giving you that beautiful browned color. And browning the butter brings out this nutty aroma and caramel, toffee-like flavor that can’t be beat.
And if you’re new to browning the butter – don’t worry it’s easy to do. You will melt down the butter on the stovetop and once it’s melted you let the butter continue to cook.
I love using browned butter in my baking! Like in my brown butter brownies, browned butter chocolate chip cookies, and these brown butter pumpkin cookies. It’s such a game changer!
For a full tutorial on browning the butter, click here.
How To Make These M&M Cookie Bars- Step By Step
Brown the butter
You want to brown the butter before you start making these bars and allow it to cool slightly before making the rest of the recipe. Here is a step by step photo tutorial for you so you can make your own browned butter for these blondies.
Mix the dry ingredients
Mix together the dry ingredients in one bowl. For the dry ingredients, I always recommend whisking them together. I rarely sift the dry ingredients unless I am making a complicated cake.
For these M&M bars, whisking the flour, baking powder, and salt together is sufficient.
Mix the wet ingredients together
In a second mixing bowl, stir together the browned butter you made from earlier, brown sugar, eggs, and vanilla until smooth.
Mix together the dry and wet ingredients
At this point you are so almost there. I add my dry ingredients to my wet ingredients. Always be sure to not overmix. I like to leave a few streaks of flour left behind.
Don’t worry those streaks will get baked right in. And since you are adding in the M&M’s and chocolate chips, you will end up giving the batter a few more stirs.
Stir in the mix-ins
Add in your chocolate chips and M&M candies. Just give the batter a couple more stirs. Be sure to not over stir which can result in a cakey M&M bar instead of a chewy one.
Bake the M&M bars
You will bake these in a 13×9 pan. You want to bake these M&M cookie bars for 22-25 minutes. They may appear not done at this time, but taking them out during that time, ensures you won’t overbake them!
Recipe Variations
You can definitely customize these M&M bars. Try a different candy or chocolate. I’ve made a Reese’s pretzel version. But try swirling in some caramel sauce or nutella. Got nuts. Ooh…nuts.. those would be good too.
I also have made a version where I basically cleaned out my pantry and decided to just throw in everything but the kitchen sink and make the best blondies ever.
Recipe Tips
- Be sure to measure your flour correctly. Overmeasuring can result in a cakey texture instead fo the perfect chewiness that we are going for. You can get the full tutorial on how to measure your flour here.
- Make sure your ingredients are room temperature, like your eggs. To bring your eggs to room temperature quickly place them in a bowl of warm water for 10 minutes.
- Do not overbake. They may appear not done at this time, but taking them out during that time, ensures you won’t overbake them!
- Once they have cooled and set up, use a plastic knife to cut them. Plastic won’t heat up and will cut them neatly.
How To Cut These M&M Cookie Bars:
You could just bring the whole pan to your party and call it a day. No one would care once they taste one. But if you want to cut them into attractive bars here a few tips:
- First, line your pan with tinfoil and spray lightly with cooking spray. This will make it easier to simply lift out the entire pan at once and cut into bars.
- Allow them to cool. Completely. Cutting them warm is just going to end up in a GIANT disaster. Let them sit on the counter until they come to room temperature. I pop mine in the fridge to hurry up this process and help to firm up the bars before cutting. Usually at least an hour if not longer if I can wait that long!
- Use a plastic knife! Plastic does not conduct heat like a metal knife will so it will cut through the bars easily without warming up that chocolate inside! You will have nice clean cuts and pretty bars to present in the end!
Recipe FAQ’s
You can also freeze these for up to 3 months. Just make sure to cool completely. Freeze solid and then place in an airtight container.
You can store these bars at room temperature for up to 3 days. I don’t recommend storing in the fridge as it will dry them out.
This is probably because you either over-measured the flour (use a kitchen scale for best accuracy), or over-mixed once the flour was stirred in, or over-baked them. Do not bake them longer than 25 minutes.
You absolutely can. Melted butter works great, and is much easier but I’m begging you give browned butter tons of flavor!
More Recipes To Try
You might also like to try my M&M brownies – they are so wonderfully thick and fudgy!
Or if you’re craving more blondies try my caramel apple blondies. They are an easy apple Fall treat topped with a caramel icing.
M&M Chocolate Chip Browned Butter Blondies
Ingredients
- 1 3/4 cups (210 g) all-purpose flour
- 1 teaspoon baking powder
- 1/2 teaspoon salt
- 3/4 cup (1 1/2 sticks, 170 g) unsalted butter browned, and slightly cooled
- 1 cup (213 g) packed light brown sugar
- 1/2 cup (100 g) granulated sugar
- 2 large eggs room temperature
- 4 teaspoons vanilla extract
- 1 cup (170 g) M&M candies
- 1 cup (170 g) semi-sweet chocolate chips
Instructions
- Adjust oven rack to middle position; heat oven to 350° F. Line a 13 by 9-inch baking pan with either foil or parchment, leaving enough overhang to help you lift the blondies from the pan when they're done. Spray with cooking spray and set aside.
- Whisk flour, baking powder, and salt together in medium bowl; set aside.
- In a second mixing bowl, whisk together the butter, eggs, sugars, and vanilla.
- Stir flour mixture into butter mixture just until combined. Fold in M and Ms and chocolate chips. Spread batter into pan.
- Bake until top is shiny, cracked, and light golden brown, 22 to 25 minutes; do not overbake. Cool on wire rack to room temperature. Remove bars from pan by lifting foil overhang and transfer to cutting board. Cut into 12 large or 16 small(ish) bars and serve.
Video
Notes
- Be sure to measure your flour correctly. Overmeasuring can result in a cakey texture instead fo the perfect chewiness that we are going for. You can get the full tutorial on how to measure your flour here.
- Make sure your ingredients are room temperature, like your eggs. To bring your eggs to room temperature quickly place them in a bowl of warm water for 10 minutes.
- Do not overbake. They may appear not done at this time, but taking them out during that time, ensures you won’t overbake them!
- Once they have cooled and set up, use a plastic knife to cut them. Plastic won’t heat up and will cut them neatly.
WOW these knocked the socks off of the whole party
OH wow that’s so awesome!! Thank you Hannah! So happy to hear that!!
Made these with Christmas M&Ms and they’ve been a HUGE hit with the fam! It’s nice having an easy dessert recipe that doesn’t require getting out the stand mixer or even the hand mixer.. which means fewer things to have to clean afterward. I was lazy and used the microwave to brown my butter so this was super simple. Thank you!!
So glad you loved these! Yes that’s how I feel too- less dishes always puts a smile on my face!
hi. I only have 3 steps – heat oven/prepare pan, mix dry ingredients & bake. Nothing on the wet ingredients or the M&Ms. Thanks.
Hi Barbara! Not sure how that happened but it’s all fixed now. Thank you for letting me know!
Hey Heather, your opt-in on the left sidebar won’t go away so I can’t see the recipe, except going line by line.
Hi Jere, we’re you viewing on a phone or desktop? And was it a pop up? Thanks!
I’m a total amateur baker but this was super simple and turned out AMAZING!!
These. blondies. are. everything. I make these all the time. I have shared your recipe countless times because they are THAT GOOD. Many, many thanks!
Omg I love comments like this! You made my day Megan. And thank you for spreading the word, that means so much.
Oh yes, these are the best! Looks delicious and damn sure they taste incredible! My kids can’t get enough treats like these and I need to make these soon for them. They”’ love it
Thanks Jo! Oh yes they are incredible. Your kids will love these.
Wow you video is fantastic! Want to make these with my niece. Thanks so much for sharing :).
Thanks Daniela! I hope you and your niece enjoy them 🙂
This is such a classic. It always makes me think of bake sales when I was younger, so when I eat them I feel like a kid again!
Nothing wrong with that Leslie! Enjoy 🙂
YUM! I’m all about browned butter and I bet it gives these a wonderful flavor! They’d all be gone in an instant!
The browned butter really does up the flavor of these 🙂 Enjoy Kathryn!
I love everything with M&M’s! Especially a nice batch of chewy blondies! They are going to be a hit for a birthday party! Saving it!)
Wonderful! Thanks Veronika 🙂
These M&M cookie bars bring back school cafeteria memories ,I love these but have never tried making them before. Now I’m glad that i have a recipe 🙂 Thanks for sharing !!
Thanks Analida! Your cafeteria served better stuff than mine hahah..enjoy!
Blondies are a classic, I love that you added M&Ms to them too. They look delicious! Thanks for sharing your recipe and tips!
I am always asked what is in a blondie too!! They are one of my favourite things to make, but I have never made them with brown butter before. This is genius!!
One of my husband’s favourite desserts is homemade blondies! He would absolutely love it if I made these cookie bars for him.
Oh my gosh Corina he would love these. And my fiance is the same..he devours these!
My daughter is an M&M fiend, so she would definitely go crazy over these! I think it would be fun for her and her sister to make them together! I’m sure they’d save me one…right? 😉
Oh Sherri then your daughter is going to love these! They are easy to make too, so I know she will enjoy making them. I hope they save you one 😉
I love blondies! And that you added M & M’s AND chocolate chips, that just makes me love them even more! I can imagine that these blondies would fly off the platter at a party!
I have made all kinds of versions but these might be my favorite. And they definitely disappear at a party quickly. Doesn’t hurt that they are quick to throw together too 🙂
I have only just recently tried brown butter!! OMG what a difference it makes in baking. These would be gone in a flash for sure.
Hi Gloria! It really does make a huge difference doesn’t it? And yes these will be gone for sure. 🙂
A batch of these and I might aaaaalmost be as happy has you were on the beach. Almost. These look so soft and chocolaty and amazing!
Karly! Thank you! Yea, they might be a close second to the beach 😉 maybe a blondie in one hand while sitting on the beach now we’re talking!